D01.13 - A New Three-Phase Multi-Mode AC/DC LLC Converter with Output-Controlled Active Rectifier (with V2G and G2V Functions) for Fast DC Charging Application

This paper proposes a new three-phase multi-mode AC/DC LLC converter with output controlled active rectifier for electric vehicle (EV) fast DC charging application. In the proposed approach, two low-frequency bidirectional switches at the primary side in each phase of the converter allows vehicle-to-grid (V2G, i.e. DC/AC mode) and grid-to-vehicle (G2V, i.e. AC/DC mode) modes. When the proposed converter operates in AC/DC mode, each phase consists of an integrated bridgeless boost power factor corrector and a LLC resonant converter at the primary side. Output voltage regulation is managed by switches on the high frequency transformer’s secondary side output rectifier in each phase, with soft-switching operation achieved in all the switches. When the proposed three-phase converter operates in DC/AC mode, each phase consists of a zeta based resonant converter cascaded with a half-bridge grid-side inverter. The description of the proposed converter is explained in this paper. Results on a 480VL-L/400Vdc, 30kW design are given to confirm the functionalities of the proposed converter.